Apparatus for making paper



Oct. 21, 1941. c v

APPARATUS FOR MAKING PAPER Filed March 5, 1939 Patented Oct. 21, 1941UNITED STATES APATENT OFFICE APPARATUS z'i R l zzxlNG PAPER Elzy EarlCovey, Niagara Falls, N. Y.

Application March 3, 1939, Serial No. 259,587 In Canada March 23, 1937 1Claim.

cloth of much shorter length than that at pres-, ent used in papermaking machines; with elim ination of the many supporting tube rolls nowrequired, thereby reducing wear on the cloth to a large extent andpermitting a much more rapid and convenient replacement of worn cloths.Further objects are to insure delivery to the wire of pulp in which thefibres are uniformly distributed and heterogeneously aligned, toprothrough a-pipe 4 having a valve 4', 5 a flow table for feeding thepulp onto the wire 2 at a point in its upward travel on the cylinder andsomewhat above the centre thereof, 6 a suction box carried by a frame Iwithin the cylinder I opposite the point of impingement of the pulp onthe wire and-adapted immediately to extract water therefrom to form apaper web on the wire, and 8 an additional suction box also carried byframe I at a point above suction box B'within cylinder. I and adapted toextract further excess water from the paper web.

The cylinder I is mounted for rotation, by

lneans of bearing flanges 9, in semi-circular bearvide for continuouscontact with the wire of a relatively small volume of flowing pulp andimmediate withdrawal of water therefrom, to provide for more than onesuch flow of pulp to the wire and to provide for recovery of fine fibresfrom the white water from the wire. Another object is to provide meansfor readily varying the suction applied to the pulp at spaced points onthe wire. e

The invention thus contemplates conveying the pulp from one or more headboxes over a flow table, which maintains the fibre thoroughlydistributed, to impinge upon the wire at a point at which water iswithdrawn from the pulp to form a web which isthereafter subjected tothe action of suction. When more than one head box and flow table areused the water withdrawn by suction is returned with its contained finefibres to the second head box which provides pulp for superimposingadditional thickness of fibre on the web first formed.

The invention will now be described with reference to the accompanyingdrawing in which Figure 1 is an elevation of a machine in accordancewith the invention,

Figure 2 is a plan,

Figure 3 is a diagrammatic form of the invention,

Figure 4 is an enlarged detail view in elevation of a flow table gate,

Figure5 is a plan of the view shown in Figure 4, and t Figure 6 is anenlarged plan of a battle arrangement in a flow channel.

Referring to Figures 1 and 2, I is a perforated cylinder, on which theusual endless wire cloth view of a modified 2 travels, 3 a. head boxsupplied with pulp stock ings I0, and is driven by means of gears II ateither. end of the cylinder, chains I 2 and gears I3 on a driven shaftId.

The flow table 5 is adapted to deliver continuously a relatively smallvolume of pulp to the wire 2 and includes means for uniformlydistributing and heterogeneously aligning the fibres in the pulp as itflows thereon so that there is delivered to the wire at a constant rate,in uni form suspension in the water, a mass of fibre sufficient to formthe desired web upon contact with the wire where the water is removed..To this end, a series of channels l5 are provided on 'the flow table bymeans of a plurality of longitudinal partitions I6. The two outsidepartitions extend to the endof the flow table and the re mainingpartitions extend to within a short distance from the end whereby thepulp unites in a single stream just prior to its impingement on the wire2. The pulp flows into each channel from head box 3 through openings I!each independently adjustable by means of gates I8 slidable in verticalmembers l9 and movable by means of a screw 20, which extends through a.cross member 2|, and nut 22. The independent adjustment of openings llprovides a ready and accurate means for overcoming any lack ofuniformity in the formed paper web by regulation of the pulp flowatfixed points. 7 Two series of oppositelyinclined baliles 23 areprovided in each channel I5 adjacent the lower end thereof to agitatethe pulp just prior to its contact with the wire and thus toheterogeneously align the fibres whereby a much stronger web is formed.

A means 211s provided for shifting flow table 5 back and forth to permitaccess to the adjoining side of cylinder I and to provide adjustment ofthe table and comprises a pair of pinions 25 carried by a shaft 26mounted in a frame 21 operable by handwheels 28 and meshing with racks29 carried by the under surface of the table.

Owing to the substantially immediate extraction of water. from the pulpon its contact with the wire cloth, a pulp of greater density than usualis preferably used and a wire cloth of approximately fifty per cent lesslength than that required in ordinary paper machines may be employed.The usual number of supporting tube rolls are also eliminated and thusdrag of the cloth on such rolls, with resultant wear on the cloth, isavoided. Thus, not only do such shorter cloths require more infrequentreplacement, but the actual replacement is conveniently accomplished ina much less period of time than that ,required for the longer and morecumbersome cloths.

In some instances, when a thicker paper web is required or when one ormore layers of pulp of a different grade or color are required in theweb, one or more additional head boxes, as indicated at 33, may beprovided. Pulp is supplied to head box 33 by means of inlet pipe 3|having a connection with pipe I by means of valve 32, for admission of,pulp of the same grade as that supplied to head box 3, and a connectionwith a second pulp supply pipe 33 by means of valve 34 for admission ofpulp of a different grade, if desired. Pulp is delivered from head box30 onto the wire 2, by means of a flow table 35 of similar constructionto that of flow table 5, at a point slightly above the point of deliveryof flow table 5, a corresponding suction box 36 also supported on frameI intermediate suction boxes 6 and I being provided within the cylinderI. Shifting means 31, similar to shifting means 24, is provided fortable 35.

Suction boxes 6, 3 and 36 are connected to a header 33' of a vacuum pump38 by respective pipes 33 having valves 40 whereby the suction appliedto the wire at each point may be regulated as required, A relief valve40' is provided in header 38' whereby regulation of the vacuum appliedto the pipes 39 may be effected.

When pulp of the same grade is being delivered to the wire from at leasttwo'head boxes, an im-' portant feature of the invention resides in therecovery of line fibres from the white water drawn of! by vacuum pump33. This white water is fed into a chest 4| from whence it is pumpedthrough a line 42 having a valve 43 into the second head box 30. Sincedelivery of pulp from head box 30 is made unto the outer surface of aweb already formed on wire 2 the fine fibres are not again drawn throughthe wire and are substantially retained in the web.

While the arrangement of the wire 2 on a perforated cylinder ispreferable in that frictional wear of the wire by direct pressureagainst suction boxes is eliminated, the invention may be readilyapplied to a system such as illustrated diagrammatically in Figure 3,wherein the wire 2 travels on rolls 44 with a similar arrangement ofsuction boxes and flow tables.

The supply of pulp to each head box is under a constant pressure, whichmay be substantially high, since the machine described, in view of therelatively small continuous volume of pulp delivered to the wire and theimmediate withdrawal of water therefrom, is capable of a more rapid webformation than machines of the usual type.

It will be noted that the inlet pipes 4, 3| and 33 are of a. largerrelative size than is usual since such pipes will accommodate theincreased stock pressure without causing undesirable currents andresultant lack of uniformity in the stock on the flow tables.

I.claim:

In a paper making machine having a perforated cylinder, a travellingpaper web forming member on said cylinder, a head box adjacent thereto,a flow table slightly inclined in a downward direction and leading fromthe top of the head box to said member on the cylinder, said tablehaving a plurality of longitudinally extending channels thereonterminating short of the lower end thereof, independently adjustablegate means for admitting a controlled shallow stream of pulp from thehead box into each of said channels, a plurality of series ofpulp-engaging inclined baflles in each of said channels adjacent saidlower end, said baiiles being inclined to the direction of flow of stockand the bailies in one series being oppositely inclined with respect tothose in adjacent series, said streams of pulp being adapted to flow bygravity down said table and to unite in a single stream at thetermination of said channels for delivery onto said member, and vacuummeans within said cylinder for extracting water jfrom the pulp stream atsubstantially its point of contact with said member.

ELZY' EARL COVEY.

